I'm another player who generally finds the stock 3 band eq, a little too bright and scratchy.

Another thing you may try to move away from the typical MM sound is to lower the HPF frequency that is at the input. There is quite a decent bass roll-off below 100Hz (if memory serves) with that preamp. Increasing either or both of those 8n2 caps will lower that rolloff.

According to my graphs, it's actually more like 60Hz, not 100Hz. Amd IMO, EVERY bass should have this! I had to install one onto the P pickup of my P-Ray because without it, changing from the MM pickup to the P meant going from articulate and punchy to, well, a pregnant elephant wallowing in a pool of mud.

Or you could throw a Cave Tighter Arse in the chain so it gets applied to every bass you own.

Just found an old spice model I did of this pre. We can split the difference mate. The roll-off is from 80Hz. And I agree with a little bass roll-off for sure. I usually design something in there. A pre that goes down to DC is going to kill speakers, especially with slap playing. I was only really talking about tweaking it. I think you could quite safely lower this point down to 40-30hz for a little more oomph with finger style. But that's a personal choice of course. As you would know, speakers usually have quite a low end roll off as well...

That is interesting, so what does this resonant peak do? Do you just get a little extra boost in that region?

Well it seems inherent in the Neo speakers I've seen. And the real effect is simply that it forces cab designers to address this with their crossover design, and tweeter choice. So this low treble is a region that varies a lot when you try out different neo cabs and if you have a bass that has a big old peak right there, then you'll really hear that difference when you are at the Bass Centre in their amp room!

MM pickup to the P meant going from articulate and punchy to, well, a pregnant elephant wallowing in a pool of mud.

So you have this pre in your P/MM bass? And the P sounded muddy. Well, that cap might be part of that, man. On a P pickup it will give you a peak in the upper mids, then roll all the treble off. Without seeing your exact setup it's hard to say though. Just thinking out loud really...

So the old sizzly ray was designed for muddy speakers?

Well, I suppose so. I'm no Musicman historian, but bass speakers back then rarely had horn tweeters like they all do today. In the early 90's, the rage was to have a 2-10 speaker as your top box, with a x-over for your single 15 cab (GK BiAmps baby!) A 10" bass speaker won't really produce much above that 2Khz stingray peak anyway, so I guess it makes sense.

Haven't looked at the other thread, but just tried removing the LPF cap. Sounds awful! Completely unusable for what I want to hear. Really thin and scratchy.

I've been doing some crude freq plots as I've tried different things, to compare visually, along with the listening. I've done these by playing each open string and letting it ring out, with peak hold engaged.

First one is the stock 3 band flat.

Second is with the 2.7n cap replacing the 2.2n. I liked the sound of this one.

Hmm that's interesting. The removal of the LPF seems to introduce plenty of everything between about 7K and 13K, so no wonder it sounds scratchy.

I'm liking the look of the 2.7n cap. Smoothes out 4K, which is what you wanted. But it also seems to give it some extra in the low mids at 300Hz or thereabouts, and across most of the mid band. For loud band work, which is what I do, that's a good thing.

Hmm that's interesting. The removal of the LPF seems to introduce plenty of everything between about 7K and 13K, so no wonder it sounds scratchy.

I'm liking the look of the 2.7n cap. Smoothes out 4K, which is what you wanted. But it also seems to give it some extra in the low mids at 300Hz or thereabouts, and across most of the mid band. For loud band work, which is what I do, that's a good thing.

Actually I made a mistake and that's a 3.3n cap as the LPF.

That extra 7k to 13k, is everything I don't like about the 3 band eq multiplied by 10.

Here it is with a 2.7n LPF and a 15n cap replacing the 8.2n on the input, to lower the HPF cutoff.

Ha Ha, for sure. Directly buffered pickups will all sound hifi like this. I really meant it as a jumping off point. Definitely read my other posts again - on both forums - for ways to tune the response at the front end of this circuit. That cap really is a big part of "the stingray sound". Removing it gives the pre more or less a flat response (with the three tone pots in the middle, that is). But because there's no pot(s) in between the pickup and the pre, the resonance of the pickup will jump right up, probably to around 10khz.

If you like the flatter less peaky response with the cap removed, but want a more warmer, natural tone, then put a resistor in there instead. This will lower the input z. I'd start with a 100k. Or better still, try a temporary pot, or even a trimpot wired to the board.

Winders usually design pickups with the load from a pot or two in mind. A couple of 250k pots will hugely tame any resonances that high inductance pickups have. That's the real beauty of the original 2-band pre that Leo designed in the 70's. The treble contol does not cut and boost symmetrically. It cuts far lower than it boosts, so you can really tame that treble.

As I mentioned on TB, if you want a resonant peak, then try different caps until you find the frequency you like, then with an in-line resistor you can adjust the height of that resonance. Unlike you, the poster there wanted to raise that peak, and also tame it a little. He initially asked for more treble boost from the active tone pot. With that cap rolling off from that low treble peak, there's little high treble left for the pot to boost! So I suggested altering the response of the front end instead.

These days on my stingray, I have an active resonant filter that I can sweep. Gigging, I usually have it set somewhere between 4 and 6khz, a good octave higher than the peak the 2n2 cap gives you. And the peak is more like 6-8dB. But I also have a push-pull that simply puts a 2n2 right across the pickup if I really want that old-school late-80's clanky 3-band tone.

Yes, I saw the guy was wanting it brighter. Mustn't have tweeters in his cabs.

I'm not hearing (or seeing) any resonant peaks with the larger caps as the LPF, where I do with the 2.2n. Not sure why that would be? I didn't want to change the 'ray tone, just make it less clanky and thin in the high mids. This is working well for me. If someone handed me this, as it is now, I would be quite happy to play it and have no real complaints.

I'm still playing with the mids. I'm considering adding a toggle switch to select between 3 different caps. The main reason not to do it, is I love the way you can turn the control plate over on a 4 string 'ray and the pots fit perfectly over the cavity and side of the bass, so you can work on it.

No Idea why you can't hear this. By my ear it is very prominent, and goes some way to defining "the stingray sound". But hey, there's all sorts of variables, plus of course we all hear things differently. I'd recommend recording some riffs and playing around with a resonant LPF in your DAW of choice. Set the Q around 4, for a 12dB peak and sweep between say 1khz and 4khz. This is the region that tweaking this cap will effect.

I just checked my stingray, and the cap I have switching across my pickup is actually 1.5n. I also have the input z limited to 1M when that cap is switched in, so the result is a peak that's slightly higher in freq, and slightly lower in resonance than the true 3-band setup. But it still let's me go back to that 90's stingray vibe when I pull the switch. (Fwiw, my sweeping resonant filter is also disabled with that switch - it's a push-pull on the filter knob.)

Unfortunately I'm moving house right now, otherwise I'd put together some sounds or a vid to demo these things.

(or seeing)

I'm guessing you can't see this in your spectrum sweeps because once the attack of the note has finished and the string is just ringing out, there's very little action happening above 1.5khz to speak of. Perhaps you could record some transients and analyse these?

I'm still playing with the mids

Personally, I'm not sure I'd spend to much time tweaking the mid control on a 3-band baxendall like this. It has a very broad bandwidth (iow low Q), and little cut and boost compared to the other two controls. From my spice model, with the mids at 100% and the bass and treble at centre, you get a 6.8 dB of boost at 400hz. But it rolls of at a leisurely 1.5dB/octave! (By comparison, the treble roll off after that input cap is 12dB/octave.) But mate, go for it. I'm not stopping you. Tweaking is really a great way to learn and to find your tone. I've been tweaking stuff like this since I was a boy in the late 80's! The 8n2 cap across the pot limits the upper range, and the 4n7 from the wiper limits the lower range. I'd recommend switching both caps at once, and keeping their ratio. If you try to tighten up the bandwitdth by decreasing the wiper cap and increasing the other cap, well because the Q is so low, you will start to seriously limit the cut and boost range. On my stingray pre, I have a separate active midrange control. It has 15dB cut/boost at 500hz, Q of 1.4.

Also, to avoid switching pop, use a switch that is make-before break, or better yet, devise a setup with series caps and the switch simply shorting out one.

I'm guessing you can't see this in your spectrum sweeps because once the attack of the note has finished and the string is just ringing out, there's very little action happening above 1.5khz to speak of. Perhaps you could record some transients and analyse these?

The meter is set to peak hold, so the peaks remain. You can clearly see a peak around 4k in the stock eq graph, but it isn't there with the larger caps.

The 8n2 cap across the pot limits the upper range, and the 4n7 from the wiper limits the lower range.

Is that correct? The smaller cap changing how far it goes down, with the larger one controlling how far it goes up? Or is that meant to be the other way around? When I increased the value of the 4.7n cap to the wiper, the range it was working on, was quite a bit lower.

yep, the cap across the outer pot lugs limits the upper range. that's why there's not one on the treble pot. the upper range of the treble is limited by both that resonance cap at the input, plus the cap on the feedback loop of the second opamp.

by increasing the wiper cap in the mid, you are lowering the centre frequency, but also increasing the bandwidth and the cut/boost amount.